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Unlike other languages, JavaScript considers "function" as an object:

typeof Object // "function"

class Test {}

typeof Test // "function"

But null returns a "object":

typeof null // "object" => bad

If you need to consider intrinsic "object", you'll need to get it from prototype:

typeof Object.prototype // "object"

typof Object.__proto__ // "function"

__proto__ is an internal function. But prototype is a mechanism to get its parent definitions. So, using __proto__ will return the type as a function while prototype will return object checking its definition.

So, calling Object.prototype is nothing but it's just getting the name from it's constructor Object.prototype.constructor.name.

So, if you do deeper drive, then you'll get "object" after following __proto__:

typeof Object.__proto__.__proto__.__proto__ // "object"

At this point, you're at getting an object by checking it's definition. That's it. - Though, I am not able to clear up things to you.

Let me re-visit your question:

When you call typeof Object, the JS will run its __proto__.

So,

typeof Object

// evaluates:

typeof Object.__proto__ // "function"



typeof Object.__proto__.__proto__

// evaluates:

typeof Object.__proto__.__proto__.__proto__ // "object"

So when you call its prototype:

typeof Object.prototype

// evaluates:

typeof Object.prototype.__proto__ // "object"

This should satisfy your question 2 as well. Hope, you understand now.

And the following should throw you an error:

typeof Object.prototype.__proto__.__proto__ // TypeError

Because, at the end of its prototype chain, there's null which is considered as object in JS but it cannot read the property __proto__ of null.

Q1: why are they pointing to Function?

A1: Because they are functions. Function and Object are just constructor functions.

Q2: If everything is an object in JS, then why is Object a function?

A2: Because Object is just a constructor function.

typeof Object

// 'function'

typeof new Object()

// 'object'

And a function is a instance of Function, so that makes a function object.

(function(){}).constructor === Function

// true

Object is the constructor function of all objects. So, typeof Object==="function"

Here is a snippet for visualisation:

console.log(typeof Object)            //function (which is an object)

var object=new Object()               //An instance of Object 'class'

console.log(typeof object)            //object

console.log(object instanceof Object) //true, because object is created by Object()

Function is the constructor function of all functions (including itself...)

So, although not everything is a function, but most of Uppercase native identifiers refers to a constructor function.

Fundamentally

Functions has some code that can be executed.
Object are those which contains data.

For class Point having x and y.

class Point {

    constructor(x, y) {

        this.x = x;

        this.y = y;

    }

    isOrigin() { return x == 0 && y == 0; }

}

let p = new Point();

Answer 1

in this p is object which contains data or other functions.

p.isOrigin is function.

Similarly class Point is itself a function which when runs produces p. Thats why all classes like Object and Functions are functions more precisely constructor functions.

Answer2

If everything is an object in JS, then why is Object a function?

Same as Answer1.

Also how is a function actually implemented inside JS?

Different js engine will have different implementations. They have specifications which they need to follow.

What happens to the variables declared inside a function?

Off topic. Every function runs with a scope which holds all data for that functions.

Is a function converted into an object by JS compiler?

Not sure what are you asking.

Function and Object are both constructor function which can be used to create a function and an object respectively which is the reason typeof Function returns function

About the similarities and differences between and object and a function, consider the following points:

1. All non primitive types are objects in javascript.


2. All objects indirectly inherit from Object.prototype which inherits from null.


3. All native functions inherit from Function.prototype which inherits from Object.prototype so it means function indirectly inherits from Object.prototype.


4. A function can be called using () operator because javascript engine knows it is declared using a function keyword and it inherits from Function.prototype and have executable code, so whenever it is called, javascript engine creates a new execution context and set the this binding and then executes the function. None of that happens when you try to call an object instead an error is thrown i.e. "is not a function". So we can say that not every object is a function because not all objects inherit from Function.prototype but all objects do inherit from Object.prototype.


5. As function indirectly inherits from Object.prototype, you can treat it as an object e.g. add properties to it, create new objects from it.


6. Because a function indirectly inherits from Object.prototype, we call it an object but it is different from other objects because it inherits directly from Function.prototype and has code that can be executed.